A conventional electrical connecting apparatus of this type comprises, for example, a printed circuit board (PCB) which is provided inside with a plurality of wiring paths, and on one surface of which a circuit board having a reinforcing plate attached and a probe board is mounted, the probe board being provided with a plurality of probes on the opposite face of the surface opposing the circuit board. Between both the boards, an electric coupler such as a pogo pin connector connecting each of the wiring path of the circuit board and each wiring path of the probe board corresponding to the wiring path are disposed, the circuit board, the electric coupler and the probe board being integrated (see, for example, Patent Document 1 and Patent Document 2).
Each of the wiring paths of the circuit board is connected to an electric circuit of a tester body through sockets aligned at an outer edge portion exposed from the reinforcing plate on the one surface of the circuit board. On the other hand, to each wiring path of the probe board is connected the corresponding probe. Thus, each probe is connected to the tester body by a socket disposed at the outer edge portion exposed from the reinforcing plate of the circuit board through the electric coupler and the wiring path of the circuit board.
As schematically shown in FIG. 5, the probe board 3 to be connected to the circuit board 1 through the electric coupler 2 is formed to conform to the size of a semiconductor wafer 4 which is a device under test. On the other hand, one having a planar shape sufficiently greater than the probe board 3 is used as the circuit board 1. Therefore, such a wiring path as mentioned above which is formed on the circuit board 1 and the probe board 3 is so formed as to converge toward a smaller probe board 3 than this one disposed in the central area of the circuit board from an outer edge portion S of a generally large circuit board 1.
Because of this convergent configuration, a wiring path 6 (one of which is typically shown) of the circuit board 1 has: a first vertical path portion 6a penetrating at the outer edge portion S of the circuit board 1 in its thickness direction and to be connected to a connector 7 on the one surface; and a second vertical path portion 6b penetrating in the thickness direction of the circuit board 1 more radially inward of the circuit board 1 than the first vertical path portion 6a; and a lateral path portion 6c connecting both vertical path portions 6a and 6b. The second vertical path portion 6b opens at the one surface where the connector 7 is provided but opens at an inner area, i.e., an arrangement area for the reinforcing plate 5, rather than the arrangement area of the connector 7, so that the connector 7 is not prevented from being disposed.
As shown by an imaginary line in FIG. 5, however, when the probe board 3 is upsized so as to enlarge the probe area of the probe board 3 in correspondence to enlargement of a semiconductor wafer 4, the second vertical path portion 6b of the wiring path 6 opens at the outer edge portion S of the circuit board 1 which is the arrangement area of the connector 7. This causes a problem of interference between the connector 7 and the end portion of the second vertical path portion 6b. 
To avoid the interference between the connector 7 and the end portion of the second vertical path portion 6b, upsizing of the circuit board 1 requires remodeling of a tester head to which a probe card is attached. It is, therefore, necessitated to downsize the connector 7 in order to avoid any interference between the connector 7 and the end portion of the second vertical path portion 6b without incurring upsizing of such wring board 1.
[Patent Document 1] WIPO Publication No. 2005/106504; [Patent Document 2] Japanese Patent Appln. Public Disclosure No. 2005-17121